Speedo intermittent fault

[shieldr]

02 plate Fazer -
Hi, my problem is that my speedo needle is behaving erratically. Sometimes bouncing around when I ease off the throttle, sometimes not registering at all. Right now it's working fine but I know this won't last. Any advice much appreciated.
Ta
RS

[unfazed]

Check the cable going to the front wheel, could be damaged, if cable is intact take of the wheel and check the speedo sensor rotor in the front wheel. Lugs are often broken off and causes the problem you describe.
Picture shows old type (broken) and new type intact

[Timbollew]

I had this issue and it was the sensor rather than the drive dog (bit that spins in the wheel). I had a small split right at the base of the wire and moisture was getting in there and causing chaos. You could try sealing it up if you have a split with amalgamating tape or something as the sensors are about £130 new and rare as rocking horse shit to get second hand. Check the drive first though, easy fix if thats broken and about £16.

[HovBiker]

Same here.had this issue.sensor unit.was lucky enough to get a second hand one.problem solved.

[shieldr]

Thanks to all. Actually made time to have a proper look last night. Found badly routed sensor cable rubbing off brake disc. Hence why intermittent. Sometimes wet sometimes dry. Have moved cable and will test tomorrow. If it works I will attempt to seal it up. If not then there are a couple 2nd hand ones on eBay at around 30 quid. Thanks again for great feedback!